Interface and Structural Characterization of Buried CoSi2/Si(001) Nanoplatelets

L. A. MONTORO; A. ISAAC; L. J. GIOVANETTI; F. G. REQUEJO; A. J. RAMIREZ

MICROSCOPY & MICROANALYSIS

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2011 vol. 17 p. 1326 - 1327

1431-9276

There has been great interest in metal silicides investigation due to the potential applications as contact materials in microelectronic devices (e.g. TiS2, CoS2, NiS2) [1]. These materials have been extensively studied on the past two decades with particular notability for the cobalt disilicide. CoSi2 is a low electrical resistance material with CaF2-like structure (Fm3m), which is similar to the diamond-like structure of Si (Fd3m). The relatively small lattice mismatch of nearly 1.23% between CoSi2 and Si and the structural similarity leads to the possibility of growing epitaxial thin films and buried nanostructures along the (001) or (111) planes [2]. The knowledge of the crystal shape and of the CoSi2/Si interface is essential for the theoretical modeling of these systems because these features have important influence on the electronic behavior, in particular the Schottky barrier height. Here is presented a comprehensive high resolution transmission electron microscopy (HRTEM) investigation of buried CoSi2/Si nanostructures unconventionally obtained from a soft-chemistry method. In addition, the HRTEM images were studied by a strain state analysis method (GPA) [3] to calculate the 2D lattice distortion around the nanostructures. These results were compared with predictions as obtained by Finite Element Simulation (FE) to verify the induced 3D strain state.